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#include <stdio.h>
#include "esp_system.h"
#include "driver/gpio.h"
#include "esp_log.h"
#include "esp_err.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "esp_timer.h"

#define TAG "GPIO_DMA"

// Configuration for GPIO pin
#define GPIO_PIN        25
#define GPIO_PIN_SEL    (1ULL << GPIO_PIN)

// Configuration for DMA
#define DMA_CHANNEL     0
#define DMA_BUF_SIZE    64

// DMA buffer
uint8_t dma_buffer[DMA_BUF_SIZE];

// DMA interrupt handler
void IRAM_ATTR dma_isr(void* arg)
{
    // Handle DMA transfer completion here
    // You can process the data in dma_buffer
}

void app_main()
{
    // Initialize GPIO
    gpio_config_t io_conf;
    io_conf.intr_type = GPIO_PIN_INTR_DISABLE;
    io_conf.mode = GPIO_MODE_INPUT;
    io_conf.pin_bit_mask = GPIO_PIN_SEL;
    io_conf.pull_down_en = 0;
    io_conf.pull_up_en = 0;
    gpio_config(&io_conf);

    // Initialize DMA
    dma_chan_config_t dma_config = {
        .channel = DMA_CHANNEL,
        .owner = DMA_PERIPH,
        .lldesc = 0,
    };
    dma_queue_t* dma_queue;
    dma_queue = dma_queue_create(1, 1);
    dma_chan_handle_t dma_handle;
    dma_handle = dma_descriptor_allocate(dma_queue, &dma_config);

    // Set up DMA transfer
    dma_buffer_desc_t dma_desc;
    dma_desc.buffers = &dma_buffer;
    dma_desc.buffers_len = DMA_BUF_SIZE;
    dma_desc.direction = DMA_PERIPH_TO_MEMORY;
    dma_desc.desc = NULL;
    dma_desc.size = DMA_BUF_SIZE;
    dma_desc.sub_sof = 0;
    dma_desc.eof = 1;
    dma_desc.owner = DMA_PERIPH;
    dma_desc.start = 0;
    dma_desc.stop = 0;
    dma_desc.loop = 0;
    dma_desc.len = DMA_BUF_SIZE;
    dma_desc.size_word = DMA_WORD_SIZE;
    dma_desc.size_bit = 0;

    dma_channel_configure(dma_handle, &dma_desc);

    // Attach DMA interrupt handler
    dma_channel_set_irq(dma_handle, DMA_INT_RAW_TFR, dma_isr, NULL);

    // Start DMA transfer
    dma_channel_start(dma_handle);

    while (1) {
        // Your application code here
        // You can access the data read from the GPIO pin in dma_buffer
        vTaskDelay(pdMS_TO_TICKS(1000));
    }
}